Lagenaria siceraria (Molina) Standley is cultivated mainly for its oil-rich seeds and high nutrition value. It represents a potential source of additional income to rural women who are the main producers. However, production of L. siceraria is characterized by low yields, mainly due to beetle foliar damage. The evaluation of foliar damage on different accessions was based on Proportion of Damage Foliar (PDF) and Severity of Damage (SeDa). Of all accessions, only NI431 had were a proportion of leaves destroyed below 50%. Leaf surface damage for this accession was less than 25%. In contrast, NI227, NI219 and NI180 were characterized by more than 80% of the attacked leaves. In the following investigations, the effect of the organic manure based on beef droppings on the intensity of the foliar damage on NI431 and NI227 accessions was realized. The use of cattle droppings significantly reduced the number of leaves destroyed and the extent of damage in the NI227. Beef droppings also improved the yield of the plants of NI227. The difference in yield for NI227 between the two treatments (fertilized and unfertilized) was 33.53%. These results showed that it is possible to improve the productivity of NI227 through the use of organic manure. In contrast to NI227, Severity of the Damage was the same for both NI431 accession treatments (fertilized and unfertilized). This result showed that NI431 accession would be tolerant of insect pest and that this tolerance is related to genetic and non-nutritional factors of the soil.

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The production of indigenous cucurbits remains very low in tropical zones, mainly due to herbivorous insect damage. This study was conducted in Manfla located in the centre of Côte d'Ivoire at 400 km from Abidjan to evaluate the impact of herbivorous insects on foliar damage and agronomic parameters of Lagenaria siceraria (Molina) Standley (Cucurbitaceae). Our study revealed that nine insect species belonging to four families and three orders were responsible for foliar damage. The leaves were perforated, shredded and eaten away. The extent of foliar damage was estimated for each accession during three consecutive cropping seasons. For the oleaginous gourd accessions NI227, NI219 and NI180, over 75% of the leaf surface was regularly destroyed. For the bottle gourd accessions NI431 and NI432 and the oleaginous gourd accession NI354, leaf surface damage was less than 25%. Thirteen accessions were intermediate between the two groups of accessions cited above. There was no significant difference between fruits weight and seed weight for accessions NI431, NI432, NI354 and NI434, whether or not plants were treated with a broad spectrum cypermethrin based-insecticide (Cypercal 50 EC). However, these parameters differed significantly for accessions NI227, NI219 and NI180.